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Updated: Aug 6, 2026
04:52
Following the Dynamics of Structural Variants in Experimentally Evolved Populations
Published on: February 3, 2023
Pangenome-resolved structural variation drives adaptation and trait evolution in cucumber
Jiantao Guan1, Xiangsheng Li1, Han Miao1
1State Key Laboratory of Vegetable Biobreeding, Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences, Beijing, China.
Nature Genetics
|July 21, 2026
Summary
This study presents high-quality genome assemblies for 125 cucumber accessions, revealing genetic diversity and structural variations. These findings offer a genomic toolkit for cucumber evolution research and precision breeding.
Area of Science:
- Genomics
- Plant Biology
- Agricultural Science
Background:
- Cucumber (Cucumis sativus L.) is a vital global crop and a key model organism for studying plant development and genetics.
- Understanding cucumber genetic diversity is crucial for crop improvement and evolutionary studies.
Purpose of the Study:
- To generate high-quality genome assemblies for a diverse set of cucumber accessions.
- To analyze genetic diversity, structural variations, and their impact on local adaptation and agronomic traits.
- To discover novel genes and genetic elements associated with important traits like flowering time, disease resistance, and fruit development.
Main Methods:
- Genome sequencing and assembly of 125 cultivated and wild cucumber accessions.
- Syntenic gene family analysis and comparative genomics to identify copy-number variations.
- Cataloging and functional analysis of structural variations, including tandem duplications and insertions.
- Integration of structural variations into genome-wide association studies (GWAS) for trait mapping.
Main Results:
- High-quality genome assemblies capturing global genetic diversity of cucumber.
- Identification of 37,897 gene families and haplotype diversity shaped by geographic expansion.
- Discovery of copy-number variations linked to local adaptation, such as CsFT duplication for early flowering.
- Annotation of resistance loci and identification of CsCcu, an R gene conferring scab resistance.
- Cataloging 135,597 structural variations, with ~30% driving trait diversification.
- Identification of 172 quantitative trait loci (QTLs) for 38 agronomic traits, including a novel LTR insertion regulating fruit length.
Conclusions:
- The generated genomic resource provides a comprehensive toolkit for cucumber evolutionary research.
- Structural variations play a significant role in cucumber adaptation and trait diversification.
- This resource facilitates precision breeding for improved cucumber varieties with enhanced traits and disease resistance.
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